This invention relates to a thread rolling machine of the type in which a movable die is reciprocated back and forth relative to a stationary die in order to form threads on the shanks of fastener blanks which are fed successively between the dies. The blanks usually are stored in a supply hopper and are fed from the hopper to the dies along a track defined by a pair of parallel rails, the blanks being held in the track by an upper hold-down rail spaced above the parallel rails. When each blank reaches an injection position adjacent the dies, a pusher feeds the blank between the dies.
A machine of this type is capable of forming threads on many different types and sizes of blanks and thus is often changed over at frequent intervals to accommodate different blanks. Such a changeover not only may involve changing the dies but also may require several set up adjustments to the position of the dies, the parallel track rails, the hold-down rail and the hopper. Jackson United States Patent 3,926,026 discloses a versatile thread rolling machine in which the changeover is simplified by virtue of the stationary die being carried on a series of stacked members which are adjustable relative to each other to allow precise adjustment of the stationary die.